Stent grafts are deployed into lumens of the human or animal body to repair or protect the wall of a vessel such as to span an aneurysm in the vessel. There are situations where the aneurysms includes a branch vessel from the lumen. In these cases spanning an aneurysm can cut-off blood flow into the branch vessel which could have serious consequences for a patient. It has been proposed to provide a fenestration in the stent graft and extend a side arm stent graft through the fenestration into the branch vessel but there can be problems with the sealing of the side arm stent graft into the main stent graft. With insufficient sealing endo leaks can occur which will continue to provide pressure into the aneurysm.
It is to this problem that the present invention is directed or at least the present invention provides a useful alternative to a physician.
Throughout this specification the term “distal”, with respect to a portion of the aorta, a deployment device or a prosthesis, is the end of the aorta, deployment device or prosthesis further away in the direction of blood flow away from the heart, and the term “proximal” means the portion of the aorta, deployment device or end of the prosthesis nearer to the heart. When applied to other vessels similar terms such as “caudal” and “cranial” should be understood.